METHOD FOR PRODUCING CATALYST MOLDED ARTICLE USED WHEN PRODUCING alpha,beta-UNSATURATED CARBOXYLIC ACID, AND METHOD FOR PRODUCING alpha,beta-UNSATURATED CARBOXYLIC ACID AND alpha,beta-UNSATURATED CARBOXYLIC ACID ESTER USING SAME

Abstract

An object is to provide a method capable of stably producing a catalyst molded article which is favorable in moldability in a step of molding a dried catalyst product and which provides a high yield of α,β-unsaturated carboxylic acid, and methods for producing α,β-unsaturated carboxylic acid and α,β-unsaturated carboxylic acid ester with the catalyst molded article. The object is achieved by a method for producing a catalyst molded article by preparing a catalyst raw material-containing slurry with a catalyst production apparatus washed under specified conditions, and methods for producing α,β-unsaturated carboxylic acid and α,β-unsaturated carboxylic acid ester with the catalyst molded article.

What is claimed is: 
     
         1 . A method for producing a catalyst molded article for use in the production of α,β-unsaturated carboxylic acid, by oxidation of α,β-unsaturated aldehyde, the method comprising
 (i) a step of washing a surface of a catalyst production apparatus where a solid including phosphorus, molybdenum and an alkali metal is attached onto the surface, with a basic solution, 
 (ii) a step of using the catalyst production apparatus, to prepare a slurry A containing a heteropoly acid salt including phosphorus and molybdenum, 
 (iii) a step of drying the slurry A, to obtain a dried catalyst product, and 
 (iv) a step of molding the dried catalyst product, to obtain a catalyst molded article, wherein the basic solution after washing the surface of the catalyst production apparatus in step (i) has a pH of 9 or more. 
 
     
     
         2 . The method for producing a catalyst molded article according to  claim 1 , wherein the dried catalyst product is molded with an extrusion molding machine in step (iv). 
     
     
         3 . The method for producing a catalyst molded article according to  claim 2 , wherein the dried catalyst product is molded at an extrusion rate of 50 to 500 mm/min in step (iv). 
     
     
         4 . The method for producing a catalyst molded article according to  claim 2 , wherein the dried catalyst product is molded at an extrusion rate of 50 to 300 mm/min in step (iv). 
     
     
         5 . The method for producing a catalyst molded article according to  claim 2 , wherein the maximum value of the pressure in the extrusion molding machine in step (iv) is 15 MPa or less in terms of gauge pressure. 
     
     
         6 . The method for producing a catalyst molded article according to  claim 1 , wherein the surface of the catalyst production apparatus is washed with the basic solution being stirred at a power required for stirring per unit volume of 0.01 to 6 kW/m 3  in step (i). 
     
     
         7 . The method for producing a catalyst molded article according to  claim 1 , wherein the surface of the catalyst production apparatus is washed with the basic solution being circulated in a pipe connected to the catalyst production apparatus, by use of a circulation pump, in step (i). 
     
     
         8 . The method for producing a catalyst molded article according to  claim 7 , wherein the linear velocity of the basic solution circulated in the pipe is 1 to 100 cm/s. 
     
     
         9 . The method for producing a catalyst molded article according to  claim 1 , wherein the dried catalyst product has a composition represented by the following formula (I):
   P a MO b V c CU d A e E f G g (NH 4 ) h O i   (I)
   
       wherein P, Mo, V, Cu, NH 4  and 0 respectively represent phosphorus, molybdenum, vanadium, copper, ammonium radical and oxygen, A represents at least one element selected from the group consisting of antimony, bismuth, arsenicum, germanium, tellurium, selenium, silicon and tungsten, E represents at least one element selected from the group consisting of iron, zinc, chromium, tantalum, cobalt, nickel, manganese, titanium and niobium, G represents at least one element selected from the group consisting of potassium, rubidium and cesium, a to i each represent the molar ratio of each component, b=12, a =0.5 to 3, c=0.01 to 3, d=0.01 to 2, e=0 to 3, f=0 to 3, g=0.01 to 3, and h=0 to 20 are satisfied, and i is the molar ratio of oxygen necessary for satisfying the valence of such each component. 
     
     
         10 . The method for producing a catalyst molded article according to  claim 1 , wherein the dried catalyst product has a Keggin-type heteropoly acid structure. 
     
     
         11 . The method for producing a catalyst molded article according to  claim 1 , comprising a step of washing the surface of the catalyst production apparatus, washed with the basic solution in step (i), with water, to remove the basic solution. 
     
     
         12 . The method for producing a catalyst molded article according to  claim 11 , wherein the basic solution is removed by washing with stirring of water at a power required for stirring per unit volume of 0.01 to 6 kW/m 3 . 
     
     
         13 . A method for producing α,β-unsaturated carboxylic acid, comprising oxidizing α,β-unsaturated aldehyde in the presence of a catalyst molded article produced by the method according to  claim 1 . 
     
     
         14 . A method for producing α,β-unsaturated carboxylic acid ester, comprising esterifying α,β-unsaturated carboxylic acid produced by the method according to  claim 13 .